Tornado strikes in Oklahoma

A boy is pulled from beneath a collapsed wall at the Plaza Towers Elementary School following a tornado in Moore, Okla., on Monday. (AP Photo Sue Ogrocki)

Kim Schwab looks over her destroyed home in south Oklahoma City on Monday after a tornado struck. (AP Photo/The Oklahoman, Paul Hellstern)

A child calls to his father after being pulled from the rubble of the Tower Plaza Elementary School following a tornado in Moore, Okla. (AP Photo/Sue Ogrocki)

A boy is pulled from beneath a collapsed wall at the Plaza Towers Elementary School after a tornado in Moore, Okla., Monday. (AP Photo/ Sue Ogrocki)

A woman carries a child through a field near the collapsed Plaza Towers Elementary School in Moore, Okla. (AP Photo Sue Ogrocki)

A tornado passes across south Oklahoma City on Monday. (AP Photo/The Oklahoman, Paul Hellstern)

The Moore Medical Center and vehicles lie damaged after a tornado moves through Moore, Okla., on Monday.(AP Photo/Alonzo Adams)

Two men attempt to pry open a door on this car to check for victims in a business parking lot west of I-35 south of 4th Street in Moore, Okla., on Monday. (AP Photo/The Oklahoman, Jim Beckel)

Oklahoma City firefighters check on the status of Gene Tripp as he sits in his rocking chair where his home once stood. The house was destroyed by a tornado Monday. (AP Photo/The Oklahoman, Chris Landsberger)

Glenn Rusk hugs his neighbor Sherie Loman outside her home north of Briarwood Elementary School after a tornado moved through Moore, Okla. (AP Photo/The Oklahoman, David McDaniel)

Kay James holds her cat as she sits in her driveway after her home was destroyed by the tornado that hit at Oklahoma City. (AP Photo/The Oklahoman, Chris Landsberger)

Allen Anderson surveys the damage to his home. A monstrous tornado roared through the Oklahoma City suburbs Monday. (AP Photo/The Oklahoman, Steve Sisney)

JoAnn Anderson sorts through the rubble of her home after a tornado struck in Moore, Okla. (AP Photo/The Oklahoman, Steve Sisney)

Rescuers recover a horse from the remains of a day-care center and destroyed barns in Moore, Okla. (AP Photo/The Oklahoman, Steve Sisney)

A woman carries an injured child to a triage center near the Plaza Towers Elementary School in Moore, Okla. (AP Photo Sue Ogrocki)

A woman is pulled out from under tornado debris at the Plaza Towers School in Moore, Okla. (AP Photo Sue Ogrocki)

Parents reunite with their children at Briarwood Elementary school after a tornado destroyed the school in south Oklahoma City. (AP Photo/The Oklahoman, Paul Hellstern)

Workers look for victims under debris from a tornado that passed across south Oklahoma City on Monday. (AP Photo/The Oklahoman, Paul Hellstern)